Ever since Comcast unveiled its plan to take over the nation's second biggest cable company, liberals have been pretty upset about the idea. Among the most vocal is Sen. Al Franken (D-Minn.), who argued recently in blunt messages to federal regulators that "the Internet belongs to the people, not huge corporations." On Tuesday, dozens of left-leaning organizations, such as Moveon.org and SumofUs, sent a letter to the Justice Department and the Federal Communications Commission expressing their displeasure.

Conservatives, by contrast, have mostly kept mum or praised the looming merger. But that may be starting to change as Republicans detect a  political opportunity in the proposal — not to mention some burgeoning problems with the merger itself. The result is bipartisan objection to a buyout that critics say would be harmful to competition.

Comcast has argued that when stacked up against wireless companies and DSL providers, the cable company is surrounded by plenty of potential rivals. But as my colleague Cecilia Kang points out, the variation in broadband quality when it comes to these other services means that Comcast isn't really going head-to-head with these guys. Cellular data plans top out at speeds of roughly 10 Mbps, while cable can outpace that easily. Cable remains the most common way that Americans connect to the Internet, with more than half of all U.S. households getting online through a cable provider. And if the Time Warner Cable deal gets approved, almost 60 percent of all U.S. cable subscribers would belong to Comcast.

Republican groups, including the American Family Association, Tea Party Nation and the U.S. Business and Industry Council, see that consolidation as a reason to worry.

"Competition isn’t just about the number of competitors," they and nearly a dozen other organizations wrote to Congress Tuesday. "It is also about the market forces that stimulate the process of bringing new and innovative products to the market that consumers want."

Others see the merger as a chance to score points against the Obama administration, which has close ties with top Comcast execs Brian Roberts and David Cohen. The right-leaning Washington Free Beacon published a 1,200-word column on Friday excoriating Comcast's political contributions to Democratic politicians. That was soon followed by columns on Breitbart.com and a number of other outlets.

"If Republicans had any sense, they would wage war against Comcast and its Democratic enablers and turn the merger into a live issue," wrote the Free Beacon's Matthew Continetti.

Just because conservatives are beginning to line up alongside their liberal counterparts doesn't mean they'll be able to torpedo the deal. Neither does the White House's relationship with Comcast necessarily imply that the Justice Department and the FCC are in Big Cable's pocket. But the right's growing skepticism is a surprising turn for a party that tends to side with business as a matter of instinct.