WASHINGTON (AP) -- Congress returned Monday to potentially incendiary fights over nominations, unresolved disputes over student loans and the farm bill, and the uncertainty of whether lawmakers have the political will to rewrite the nation's immigration laws.
The cooperation evident in the Senate last month with passage of a bipartisan immigration bill could be wiped out immediately if Majority Leader Harry Reid, D-Nev., frustrated with GOP delaying tactics on judges and nominations, tries to change the Senate rules by scrapping the current three-fifths majority for a simple majority.
Republican leader Mitch McConnell of Kentucky has indicated it's a decision Reid could regret if the GOP seizes Senate control in next year's elections.
"Once the Senate definitively breaks the rules to change the rules, the pressure to respond in kind will be irresistible to future majorities," McConnell said last month, looking ahead to 2014 when Democrats have to defend 21 seats to the GOP's 14.
McConnell envisioned a long list of reversals from the Democratic agenda, from repealing President Barack Obama's health care law to shipping radioactive nuclear waste to Yucca Mountain in Reid's home state of Nevada.
Recently elected Democrats have clamored for changes in Senate rules as Obama has faced Republican resistance to his nominations.
Two Cabinet-rank choices -- Tom Perez as labor secretary and Gina McCarthy to head the Environmental Protection Agency -- could be approved by the Senate this month after a loud debate over administration policies.
The GOP also has challenged Obama's three judicial nominees to the powerful U.S. Court of Appeals for the District of Columbia Circuit as they've tried to eliminate the vacancies. The Senate scheduled a vote late Monday on a less contentious nomination -- Gregory Phillips to serve as U.S. circuit judge for the 10th Circuit.
Reid had served notice in April that the Democratic majority could change the Senate rules on "any given day," and he was willing to do so if necessary.
In the Republican-controlled House, courteous behavior, even within the GOP ranks, has barely been perceptible with the ignominious failure of the farm bill. Some collaboration will be necessary if the House is to move ahead on immigration legislation this month.
Conservatives from safe, gerrymandered House districts have rebuffed appeals from some national Republicans who argue that embracing immigration overhaul will boost the party's political standing with an increasingly diverse electorate, especially in the 2016 presidential election. The conservatives strongly oppose any legislation offering citizenship to immigrants living here illegally.
Reflecting the will of the rank and file, House Speaker John Boehner of Ohio and other Republicans have said the comprehensive Senate immigration bill that couples the promise of citizenship for those living here unlawfully with increased border security is a nonstarter in the House.
Opening the Senate session on Monday, Reid urged the House to consider the Senate bill -- a highly unlikely step.
"Now it's our duty to convince our colleagues in the House, yes, they should vote with us. Bipartisan immigration reform that includes a pathway to citizenship makes economic and political sense," Reid said.
House Republicans were assessing the views of their constituents during the weeklong July Fourth break and planned to discuss their next steps at a private meeting Wednesday.
Rep. Michael McCaul, R-Texas, chairman of the House Homeland Security Committee said Republicans would be hashing out "two key hot spots" in the meeting: the pathway to citizenship and health care.
"We need to be the party of solutions and not always obstructing. And, so, I think there's an effort here that we have a broken immigration system. We need to fix this immigration system," McCaul said Sunday on CBS' "Face the Nation," predicting that the full House could take up immigration as early as this month and representatives from both chambers could be working to resolve differences in the House and Senate versions late this year or early next.
The House Judiciary Committee has adopted a piecemeal approach, approving a series of bills, none with a path to citizenship that Obama and Democrats are seeking. Democrats hope the single-issue bills get them to a conference with the Senate, where the prospects for a far-reaching overhaul improve.
"I think what you're finding is that there will be a compromise, a smart compromise," Rep. Xavier Becerra, D-Calif., said Sunday, also on CBS. "You have to be smart. You have to be tough. But you have to be fair. And if you can do that, you'll have a full fix."
A more pressing concern for some lawmakers was the fate of the five-year, half-trillion-dollar farm bill.