WASHINGTON (Reuters) – Barack Obama‘s presidency has been a wild ride for the US Congress and lawmakers are bracing for more turbulence when they begin returning yesterday to tackle an array of tough issues from healthcare to energy.

In the three months since Obama took office, his fellow Democrats in Congress have overcome Republican objections and unleashed a raft of spending to try to buoy the sinking economy.

With the Senate coming back yesterday and the House in today, following a two-week recess, the Democratic leadership in both chambers will press its advantage, while undeterred Republicans dig in their heels.

“Now the agenda gets more ambitious, and by definition more contentious,” said Andrew Taylor, chairman of the political science department at North Carolina State University, noting Democrats may have trouble within their own ranks over some of the most ambitious spending proposals.

“The whole notion of deficits is going to make some Democrats uneasy,” Taylor said.

Democrats take heart from polls that show Obama remains highly popular and the public has more confidence in Democrats than in Republicans to solve the nation’s problems.

Yet there is no sign Republicans, who opposed Obama’s $787 billion economic stimulus package and $3.5 trillion budget plan, are about to cooperate with what they denounce as Obama’s liberal “tax-and-spend” policies.

Instead, they see a political opportunity — and last week aired a television and radio ad campaign targeting 43 potentially vulnerable House Democrats who they accused of endorsing “a reckless spending spree.”

The Democrats are in largely conservative districts, which had close elections in 2008 and could tip to Republicans in the 2010 midterm vote.

“We will continue to hold these Democrats accountable for rubber-stamping (House of Representatives Speaker) Nancy Pelosi’s agenda that will burden middle-class families and inflict further damage on an already fragile economy,” said Ken Spain of the House Republican campaign committee.
Democrats, who extended their control of Congress in the 2008 elections, can ram a bill through the House on a majority vote. They may face increased problems in the Senate where they need 60 votes in the 100-member chamber to clear Republican roadblocks.

With 58 votes now, Democrats need at least a couple of Republican senators to hit 60. They won over three to help pass Obama’s stimulus plan, but one of them — Pennsylvania’s Arlen Specter — faces a tough re-election challenge and may be reluctant to cross party lines again on some issues.

One of the first agenda items will be Senate consideration of a bill backed by Democrats and some Republicans to tighten laws against financial fraud.