For the past five months, real-estate tycoon Donald Trump has led all but two national polls of the Republican presidential primary.
On Wednesday, a CNN/ORC poll found him with his largest lead yet: a 21-point advantage over US Sen. Ted Cruz (R-Texas), who has been surging lately. Trump was up three points from CNN's last survey in November.
It's all part of an astounding and continued rise that has turned a candidate whose staying power experts initially dismissed into a still-overwhelming front-runner.
From the CNN poll data, it's easy to tell why. Trump has sold much of the Republican primary electorate not only on his brand, but on his ability to tackle the issues most pressing to Americans.
Perceptions of his favorability, electability, and strategy on key areas have all improved over the past six months. In many of these cases, he has seen dramatic turnarounds with the GOP electorate.
Here's a look at the shifts:
In a July CNN poll, just 51% of Republicans viewed Trump favorably, compared with 40% who saw him in an unfavorable light.
In December, 72% of registered Republicans say they view Trump favorably. That contrasts with just 27% who view him unfavorably.
In August, just 38% of Republicans thought that they would have a "better chance" of winning the presidency in 2016 if Trump was the nominee. Fifty-eight percent said that the party would have a better chance with someone else.
In December, 46% of Republicans now see a "better chance" of winning the presidency with Trump as the nominee. That number has climbed to an almost even split with the 50% of GOP voters who think someone else would give them a better chance.
Handling the economy:
In most presidential election cycles, this is perhaps the key question: Which president will help the economy, and therefore the average voter's wallet? In June, right after Trump announced his candidacy, 20% of Republican voters thought that he could best handle the economy, compared with 16% for former Florida Gov. Jeb Bush.
Now, 57% of voters think Trump will do the best job with the economy. No other candidate comes within 45 points.
Handling illegal immigration:
This has always been a strong point for Trump with Republican voters going back to the early weeks of his campaign, when he proposed building a wall along the US-Mexico border. But in June, 18% of GOP voters thought Bush actually was best to handle the issue, compared with 14% for Trump.
In December, it's not even close. Fifty-five percent of Republican voters trust Trump most on the issue. Cruz is next, with 15%. Bush gets just 3% of the vote.
The terrorist group's attack in Paris, and the subsequent attack linked to the organization in San Bernardino, California, has pushed foreign policy and national security up on the list of priorities. In August, 32% of GOP voters thought Trump would handle the group best, compared with 16% for Bush.
Four months later, Trump is the choice of 47% of voters as the candidate who can best handle ISIS, compared with 21% for Cruz and 7% for Bush.
Trump is averaging 35.1% support in the past eight Republican primary surveys, according to Real Clear Politics. As 2015 comes to a close, Trump has led all but two national surveys since July, when he first seized control of the GOP race.
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