Except that it really doesn't. Nobody gives a fuck about winning Wyoming. NOBODY.
The big money goes where the votes are, more specifically where the MOVEABLE votes are.
Look at Iowa -- Kasich and Christie barely even acknowledged it exists, because they know they can't win there.
I'll be genuinely interested to see how much money and effort Sanders puts into SC, because frankly he can't win there unless attitudes shift dramatically within the African-American community about him.
Bush thought he could win in Iowa and burned a shit-ton of money to try and move votes. He'd have been better off not contesting the state at all, because at least then he'd have Trump's excuse of "we didn't invest much in Iowa".
In the general election, the GOP isn't going to waste money trying to win in CA, MA or NY, despite all those juicy votes because they're not moveable.
The Dems aren't going to waste money in places like OK, KS, NB, AL, MS because they're not moveable *and* there's not enough votes to be worth the effort.
The "relevant" states become the swing states with a moderately large number of votes (OH, FL, PA, NC, VA, MI). What's got to be troubling for the Republicans is that the Democrats continue to enjoy having vote-rich urban bulwarks like CA, MA and NY that they can rely on, while the traditional large red states like FL and TX are becoming more purple thanks to demographic shifts. This is why the GOP either has to win over Latinos, or somehow get rid of all of them (or at the very least, push them into blue states -- they'll lose the popular vote but might could win the electoral vote). The remaining GOP bulwarks are vote-poor rural states in the South and West.
It's created a weird system in which the least populous states are still irrelevant, but the most populous states are largely irrelevant as well, at least in national elections. The real kingmakers are the second-tier states which are populous but still have a mix of urban/rural.
When it comes to policy-making, the irrelevant states are still largely irrelevant. California has 12.1% of the US population, so it gets 12% of the House membership. Wyoming has 0.18% of the population, so it gets 1 representative (which is actually a statistical over-representation, since 1 rep=0.23%).
The Senate is the only thing that tries to keep largely uninhabited states relevant. Unfortunately, because conservatism is strongly correlated with the degree of ruralism, it tends to do this by electing Senators who think we all need rifles to protect our crops and womenfolk from coyotes and injun savages. Or who are former mining execs just looking to strip-mine the empty land. Or both.