Illinois poll shows Clinton with 51 percent support in Illinois.
A new poll shows Bernie Sanders ahead of Hillary Clinton in West Virginia.
Poll shows Trump in lead in Massachusetts, with Sanders and Clinton tied.
Clinton's lead is down from 25 points in January to 11 in a new NBC/WSJ poll.
The aide is downplaying a Wall Street Journal poll that puts Ted Cruz in the lead.
The Bloomberg poll shows Rubio and Bush in a tight race for third place.
Former Florida Gov. Jeb Bush comes in second place at 16 percent.
Rubio's support has jumped 7 points, putting him behind only Trump.
Sanders leads by huge margins with independents and young voters.
Support for both senators has risen in a new national poll.