But, just like their nearest challengers on Tuesday, a nervy Liverpool failed to hold onto their early advantage, though a point at least extends their advantage at the summit with 14 games remaining.
After James Maddison had inexplicably missed a free header from close range, Harry Maguire steered in a half-volley to make it 1-1 in first-half stoppage time.
Snow fell prior to kick-off on Merseyside, but Liverpool quickly warmed to their task. Mane's low, right-footed drive slipped across the wet surface and beyond Kasper Schmeichel's dive to put the hosts ahead.
The early strike appeared set to signal an avalanche of goals for the Reds, Schmeichel turning aside a Roberto Firmino effort before an unmarked Mane carelessly headed the resulting corner well wide.
However, Leicester posed the greater threat as the opening half wore on, eventually equalising in added time through Maguire - only booked minutes before after clipping Mane as the forward looked to run onto a throughball - as Liverpool failed to reorganise in defence after a partially blocked shot was headed back into the penalty area by Ben Chilwell.
The visitors should have been level earlier, too, but Maddison nodded Marc Albrighton's inviting cross beyond the target, letting Alisson – who had turned over possession with a lazy clearing kick – off the hook.
Liverpool's goalkeeper was called into action early in the second half by one of his team-mates - Firmino spared by his fellow Brazilian after poking Maguire's low cross towards his own net.
Shouts from the Kop for a penalty were dismissed by referee Martin Atkinson when Naby Keita fell under a challenge from Ricardo Pereira but Klopp's side were below par following such a fast start.
3 - Liverpool have conceded in each of their last three Premier League home games, after only conceding in two of their opening nine home league games of the season. Slip. pic.twitter.com/MjnrUKsF66— OptaJoe (@OptaJoe) January 30, 2019
What does it mean? Reds fluff their lines after City slip
Points, not performances, are all that matter for Liverpool. A quest for a first title in the Premier League era received an unexpected boost from former boss Rafa Benitez and Newcastle, yet they wasted a glorious opportunity to move further clear of City.
Worryingly, after conceding three in their victory over Crystal Palace last time out, they again looked shaky in defence. Admittedly injuries to Trent Alexander-Arnold and Joe Gomez have left Klopp short of options - Jordan Henderson played as a makeshift right-back - but they must quickly regain the solid foundations that have underpinned their challenge so far.
Maguire makes his mark in both boxes
While his goal was crucial, Maguire's best work came at the back. The England international shackled Mohamed Salah in particular, the Egyptian failing to have a shot on target, as the Foxes became the first team from outside the 'big six' to deny Liverpool victory this season.
Van Dijk caught cold
Virgil van Dijk was fit to maintain his ever-present league record in this campaign after overcoming illness in time to feature. However, the centre-back - such a pillar of strength for Liverpool this season - allowed Maguire to escape his attention for Leicester's equaliser after Andy Robertson had needlessly given away a free-kick out wide.
Key Opta facts:
2:01 - Sadio Mane's opener for Liverpool was their quickest goal in the Premier League since April 2016, when Daniel Sturridge netted against Newcastle (1:07). Intense. pic.twitter.com/8U3dar4iwd— OptaJoe (@OptaJoe) January 30, 2019
- Liverpool failed to win at Anfield for just the second time in the Premier League this season (W9 D2), having also drawn against Manchester City in October 2018.
- Liverpool attempted just 10 shots in this game against Leicester – the only occasions when they’ve had fewer in the Premier League this season were both against Manchester City (seven, both home and away).
- Liverpool’s Sadio Mane has now scored 10+ goals in each of his five seasons in the Premier League, with eight of his 10 goals this term coming at Anfield.
- Each of Harry Maguire’s three league goals for Leicester this season have come away from home – only Wilfried Zaha (4) has netted more among players to have scored 100% of their goals in away games.
After back-to-back league games at Anfield, Liverpool head on the road for a clash with West Ham on Monday. Leicester, meanwhile, host Manchester United the previous day.