An unpredictable election year in the United States is threatening to become even more topsy-turvy as both Democrats and Republicans face uprisings from their liberal and conservative bases of support. Examples abound: President Barack Obama, on track to end the US combat role in Iraq by the end of August, is scorched by some liberal commentators for still having US troops there at all. Republicans, battling to bolster security along the US-Mexican border, face pressure from conservatives to rewrite the US Constitution to stop babies born to illegals in the United States from getting instant US citizenship. How each side deals with its base will help determine whether voters will be motivated to vote in Nov. 2 elections and ultimately, which party gets to control the US Congress. Why? Voter turnout will be key in determining dozens of competitive races across the country. Each side needs their base of support energized to stand a chance of winning, and so far Republicans are leading in enthusiasm about voting. White House spokesman Robert Gibbs this week complained that the “professional left,” the liberal voices on cable television and the blogosphere, should give Obama some credit for what he has been able to accomplish in a politically divided capital. He's pushed through Congress a US healthcare overhaul, a rewrite of financial regulations, a $862 billion economic stimulus and has stopped an economic freefall. Liberal wish list And yet, instead of talking up these issues and the need to rally behind Obama for the sake of Democratic unity, liberal Democrats complain Obama has not fulfilled everything on their wish list. He dropped a government-run insurance option from his healthcare overhaul, should have gone further in punishing Wall Street, is still fighting two wars and has not closed the US military base at Guantanamo Bay, they argue. “They will be satisfied when we have Canadian healthcare and we've eliminated the Pentagon. That's not reality,” a frustrated Gibbs told The Hill newspaper this week in remarks he later sought to temper. Liberal commentator Ed Schultz declared on his MSNBC show: “Gibbs and the White House take the base for granted, there's no doubt about it.” Democratic strategist Bud Jackson said Obama has had real accomplishments but has not delivered to the extent liberal Democrats had hoped and that they are increasingly impatient. “It could decrease enthusiasm among progressives in November, which could hurt turnout,” Jackson said. Republicans are facing a rightward tug from Tea Party conservatives to cut government spending, block tax increases, limit the role of government, stop illegal immigration and generally oppose Obama at every turn. Republicans are in awe of the Tea Party movement's energy and recognize they cannot really harness the loosely knit group of Americans angry at government. “I think ignoring the Tea Party's ideas and issues is a big mistake for a Republican running anywhere in the country,” said Republican strategist Scott Reed. As a result, Republicans looking to stay on the good side of conservatives fighting illegal immigration find themselves willing to discuss repealing the 14th amendment of the US Constitution, which Republicans helped steer to passage in 1868. The strategy could help them in November but backfire on Republicans with the growing Hispanic vote in the long run. Campaign rhetoric The drive to gin up voter turnout has also led to some over-the-top campaign rhetoric. Running for a House seat in Arizona, Ben Quayle - son of former Vice President Dan Quayle - declared in a TV ad: “Barack Obama is the worst president in history.” On Nov. 2, Americans will choose 435 members of the House and 37 of the 100-member US Senate. Political gridlock in Washington could be the outcome if, as expected, Republicans pick up seats. This would likely slow Obama's agenda on such issues as climate change legislation and make it more difficult to achieve a compromise on reducing America's soaring debt. “Republicans would try to reduce some taxes and start serious oversight of federal regulatory intrusions into traditional American freedoms - including a powerful pushback on administration regulatory efforts on climate change, illegal immigration and other left-wing agenda items,” Republican commentator Tony Blankley wrote in a column this week. And a heavier conservative presence in the House could mean Republicans would face pressure to elect a more conservative leadership in Congress, deepening the partisan divide. The current Republican leader, John Boehner, for instance, could face a challenge from a conservative like Representative Mike Pence. Steve King, a Republican Party official from Wisconsin, said at last week's Republican National Committee meeting: “It's a wonderful thing if we can take control of the House. Whether John Boehner becomes the next Speaker of the House remains to be seen, frankly.” Stephen Hess, a presidential scholar from the Brookings Institution, said the sputtering economy is a key element in the frustration among liberals and conservatives alike. “Partly it's a product of tough times,” he said. “At least reasonable people hope that when the economy is back on kilter and maybe the world is a little safer the political spectrum will be less factionalized. There'll be a better chance of moving back together.”