Rasmussen's latest poll shows Hayworth just seven points behind McCain:

Longtime incumbent John McCain now leads conservative challenger J.D. Hayworth by just seven points in Arizona’s hotly contested Republican Senate Primary race.

The latest Rasmussen Reports telephone survey of likely Arizona GOP Primary voters shows McCain ahead 48% to 41%. Three percent (3%) favor another candidate, and eight percent (8%) are undecided.

Following the announcement that Sarah Palin would campaign for his reelection, McCain opened up a 53% to 31% lead over Hayworth in January. The two men were in a near tie in November.

But now Hayworth, a former congressman turned popular local talk radio host, is a formal candidate, and anti-immigration activist Chris Simcox has quit the race and endorsed him. For McCain, the new numbers also show him dropping again below 50%, and incumbents who poll less than 50% at this stage of a campaign are considered potentially vulnerable.