If by "winning" you mean "leading", and if you mean to say that the numbers don't necessarily tell the full story, then there is an expression (with some variations) that may apply:
Figures don’t lie, but liars figure.
Statistics never lie but liars use statistics.
There are three kinds of lies: lies, damned lies, and statistics.
The quote is often attributed to Mark Twain, who reportedly gave credit to British Prime Minister Benjamin Disraeli.
These wry expressions underscore how some people will use numerical data to present a conclusion that may be factual from a strictly mathematical perspective, but in a way that is somewhat misleading. One example might be a resumé that says:
Our sales doubled in the two months when I was manager of the showroom.
when, in fact, the showroom had only sold one unit previously, and two more while the person was manager. When dealing with sales statistics, we don't usually imagine a single-unit increase when we hear the word "doubled" – but that word was chosen because it sounds more impressive than the actual results.
Such truth-bending happens quite often in politics. For example, a candidate running for reelection might boast, "Our city was once the worst city for crime, but now, we are no longer in the Top 10!" (In reality, though, the crime rate has gone up – but, because it went up even faster in 10 other cities, in terms of ranking, that city fell from #1 to #11.) Yet notice how the words were carefully crafted, so that the reality of crime being still on the rise is never even mentioned (until the opposing party runs their ad, which will probably skew the data in a similar manner, only in the other direction).