Senate Republicans last week blocked committee votes on President Obama's picks to lead the Department of Labor and the Environmental Protection Agency, infuriating Democrats who have long complained about the GOP's obstructionism.

Yet this week, Republicans suddenly dropped their opposition, finally allowing Democrats to send both nominees on to the the full Senate.

On Thursday, the Senate Environment and Public Works Committee approved the nomination of Gina McCarthy to head the EPA on a party-line vote, 10-8. On the same day, the Health, Education, Labor, and Pensions (HELP) committee voted 12-10, also along party lines, to advance Labor Secretary nominee Thomas Perez.

The EPA vote came one week after Republicans refused to even show up for a vote on McCarthy, leaving Democrats short of a quorum. GOP committee members had previously demanded that McCarthy answer a staggering 1,100 questions about the EPA — she currently heads the agency's air pollution office — and then insisted they still needed more information.

As for Perez, he finally received a vote after Republicans on the HELP committee twice postponed previous votes. Most recently, they used an arcane procedural rule to prevent the committee from voting.

That Republicans finally stopped delaying the committee votes does not mean they've suddenly been placated. Rather, they're gearing up for a battle in the full Senate, where they'll have more power to block the nominations indefinitely via threatened filibusters.

Sen. David Vitter (R-La.) has said he'll force a 60-vote threshold on Perez, and Sen. Roy Blunt (R-Mo.) has already placed a hold on McCarthy's nomination. Given that both nominees garnered zero GOP votes in committee, it's clear they'll face stiff opposition in the full Senate.

Perez's nomination in particular could prove problematic, since leading Republicans like Senate Minority Leader Mitch McConnell (R-Ky.) have labeled him a "committed ideologue," and raised questions about his tenure with the Justice Department's civil rights division.

"His willingness, time and again, to bend or ignore the law and to misstate the facts in order to advance his far-left ideology lead me and others to conclude that he'd continue to do so if he were confirmed to another, and much more consequential, position of public trust," McConnell said in a statement last week.

In response, Democrats have mulled a so-called "nuclear option" of simply changing Senate rules to weaken the filibuster and allow them to approve both nominees, even in the face of unified GOP opposition.