"The question, of course, is whether that margin will be there in 18 months when voters go to the polls," said Peter A. Brown, assistant director of the Quinnipiac University Polling Institute, in a statement. "It is worth noting that in April of 2009, almost exactly four years ago, Democrats held a 41-34 percent lead in the generic ballot, according to a Quinnipiac University poll. That probably was influenced by President Barack ObamaBarack ObamaOvernight Finance: GOP divided over welfare cuts in budget | Lawmaker loses M on pharma stock he pitched | Yellen says another financial crisis unlikely in our lifetimes Why UK millennials voting for socialism could happen here, too Overnight Regulation: EPA moves to repeal Obama water rule | Labor chief to review overtime rule | Record fine for Google MORE's 58-30 percent approval rating then. Eighteen months later, however, Republicans won a historic landslide, picking up 63 House seats."

Democrats' lead is driven primarily by the gender gap that helped propel President Obama to reelection in 2012. While men split 39-38 percent in favor of Republicans, women favor Democrats 44-35 percent. 

Democrats are also favored when voters ask who they trust more to handle healthcare, likely a key issue as the Affordable Care Act is fully implemented in the coming years. But members of the GOP are trusted more to handle the budget deficit and gun policy, while congressional leaders from both parties split voters on the overall economy and immigration.

The Democratic edge in the generic ballot does not seem to be linked to any strong public affection for the president's party. They are down on both groups, just Democrats a bit less," said Brown. "For instance voters say 62-33 percent that Republicans don't care about their needs and problems, but say the same thing about Democrats in Congress 54-41 percent."

The poll also found that while President Obama maintains a 48-45 percent approval rating, voters are unhappy with his handling of a range of policy issues. Voters disapprove of his handling of the economy 53-41 percent, gun policy 52-41 percent and immigration 50-40 percent, although Obama does fare better on foreign policy. Those surveyed approve 54-29 percent of his handling of North Korea and 55-38 percent of his handling of terrorism.