As recently as three weeks ago, Gallup's daily tracking poll showed Mitt Romney leading Rick Santorum by 20 points nationally. As of yesterday, Santorum had opened up an 8-point lead over Romney -- the former senator's largest lead to date.
At the same time, Real Clear Politics' polling averages now have President Obama leading Romney nationwide 49.1% to 43.4%, after having been nearly tied in early February. It's the largest advantage the president has enjoyed over the former governor since June 2011.
It's difficult to pinpoint exactly what caused Romney's reversal of fortunes -- there was nothing particularly important about early February -- but my colleague Will Femia put together a visual that offers one possible explanation.
As Will succinctly put it, "Just sayin'."
Also note, RCP shows Obama's lead over Rick Santorum in hypothetical match-ups to be a few points higher, but unlike Romney's support, which is deteriorating, Santorum's numbers are steadily improving against the president. It's another angle that may give nervous Republicans pause.
It's probably a coincidence, but given the above image, the Romney camp may want to rethink its choice in surrogates. Trump doesn't appear to be much of a good-luck charm.