The Economist backs the Tories. Here's their case against Clegg:
[L]ook at the policies, rather than the man, and the Lib Dems seem less appealing. In the event of another European treaty, they would hold a referendum not on that treaty but on whether to stay in or leave the EU; odd, given that they also (wrongly) want to take Britain into the euro. They are flirting with giving up Britain’s nuclear deterrent. They would abolish tuition fees for universities, which would mean either letting the quality of British higher education slide still further or raising the subsidy to mostly well-off students by increasing state funding. They are worried about climate change but oppose the expansion of nuclear power, which is the most plausible way of cutting emissions. Their policies towards business are arguably to the left of Labour’s. A 50% capital-gains tax, getting rid of higher-rate relief on pensions and a toff-bashing mansion tax are not going to induce the entrepreneurial vim Britain needs.